inventory of pests and natural enemies on cotton in ... · wars among other factors. surveys showed...

Inventory of pests and naturalInventory of pests and naturalInventory of pests and naturalInventory of pests and naturalInventory of pests and natural

enemies on cotton in lowlandenemies on cotton in lowlandenemies on cotton in lowlandenemies on cotton in lowlandenemies on cotton in lowland

production zone of Ruzizi Plain,production zone of Ruzizi Plain,production zone of Ruzizi Plain,production zone of Ruzizi Plain,production zone of Ruzizi Plain,

Kivu, Democratic Republic of theKivu, Democratic Republic of theKivu, Democratic Republic of theKivu, Democratic Republic of theKivu, Democratic Republic of the

CongoCongoCongoCongoCongo

Munyuli Bin Mushambanyi Théodore1,2

1 National Center for Research in Natural Sciences, Biology Department, CRSN-Lwiro, D.S.Bukavu, Kivu DR CONGO

2 Makerere University, Kampala UGANDACorrespondence author [email protected]

13461346134613461346

Inventory of pests and natural enemies on cotton in lowland production zone of Ruzizi Plain, Kivu,Democratic Republic of the Congo

ABSTRACTABSTRACTABSTRACTABSTRACTABSTRACT

Cotton has been an important, economic, indus-trial crop since colonial times. Several genotypesare cultivated by farmers and some companies.Cotton is very important and had played a valu-able role in the development of animal industries(cattle and poultry) in Eastern DRCongo, by pro-viding foodstuffs (cotton seed) necessary to elabo-rate rations of livestock breeds. However, a de-cline in cotton production has been observed inEastern DRCongo recently. Four years ago, a di-agnostic survey was conducted to explore the situ-ation. Constraints to cotton production and pro-ductivity observed were mainly biotic. In order tofind appropriate way to control the pests, it wasnecessary to know the pest species and their as-sociated natural enemies, in order to integratethem into a sound integrated pest managementsystem for cotton in Eastern DRCongo. Pests andtheir natural enemies were collected in main cot-ton production zones.. Arthropod predators andparasitoids identified belong to the Manthidae(Mantis religiosa), Formicidae (Formica spp.),Braconidae (Apanteles spp.), Coccinellidae(Cheilomenes lunata, Cheilomenes sulphura),Redureiidae (Rhynocoris albipilosus), Chrysoperlacarnea. Several pest species were observed be-longing to the Noctuidae, Gelechiidae, Pyralidae,Tortricidae, Chrysomelidae, Aphidae, Aleyrodidae,Pyrgomorphidae and Muridae: Order Rodentia.One of the highlights of this study was the poten-tial for integrating predators in IPM systems de-velopment for Eastern DRCongo.

IntroductionIntroductionIntroductionIntroductionIntroduction

Cotton together with coffee and tea are impor-tant lucrative, economic and industrial crops since co-lonial time (Decaene, 1948; Fisher, 1917; Jurion,1941; Knaf, 1946; Querton, 1925; Stener, 1927). Itcontinues to generate important incomes to farmersin DR Congo, through sales and export of products atthe local, regional and international markets (Anony-mous, 1983; Autrique and Perreaux, 1989; Vendenput,1981). In 1999 it was estimated by DRCongo gov-ernment (Ministry of Agriculture, Annual report, 1999)that more than 2.7% of annual income of farmers inKivu and Kasai provinces was from cotton cultivation.Several genotype belonging to Gossypium hirsutum andGossypium barbadense (Cauquil, 1986; Ahanchede,2000; Coulloud, 1989; Echekwu, 2001) are cultivatedby farmers and some companies such as �Est Agrico,CotonCongo and Cotonnière du Lac�. Cotton is veryimportant and has played a valuable role in the de-

velopment of fiber and animal industries, especially byproviding cake and other products such as seed oil andfibers (Echekwu, 2001; Miller, 1984; Finley andWikinson, 1963). Cotton is the only industrial crop cul-tivated by farmers from Ruzizi Plain. It provides themconsiderableincomes (Fisher, 1917; Jurion, 1941; Knaf,1946; Querton, 1925; Stener, 1927). However, a de-cline in cotton production has occurred and cultivationin Ruzizi Plain since 1992, due to the spread of civilwars among other factors. Surveys showed pests to bea major constraint to cotton production and productiv-ity at the farmer level (Munyuli, unpublished data). Inorder to find appropriate ways to control the pests, itwas necessary to know the pest species and their asso-ciated natural enemies in order to integrate them intoa sound integrated pest/disease management systemfor Eastern DR Congo.

Experimental procedureExperimental procedureExperimental procedureExperimental procedureExperimental procedure

Pests and their natural enemies were surveyedduring the rainy and dry seasons of consecutive sea-sons of 2000-2001, in the main cotton production zonesof the Ruzizi Plain: Kiliba, Luvungi, Kamnyola, Sange,Kamvimvira, Makobola, Lemera, Kiringye, Bwegera andMulongwe. Ruzizi plain (100 x 125 km) (28°-29° E,2°-3° S; 700-900 m), is located along aside Ruzizi riveron the North of Lake Tanganyika (Figure 1). The aver-age population density is 300 inhabitants/km². It is asemi dry area with clay-loamy soil and grasslands ofImperata cylindrica and Digitaria sp. The climate ofthe area is dry tropical type Aw4 of the climatic classifi-cation of Vladamir Koppen. Two main seasons, the longrainy season (September-March) followed by the dryseason (April- August) are experienced. The rainfall pat-tern is bimodal, and the area receives an annual aver-age rainfall, which varies between 700 and 1100 mm,with average temperatures of 24 °C and a mean rela-tive humidity of 69% (Munyuli, 2002). Several ethnicgroups live there, including Babembe, Bashi, Bavira,Bafulero and some migrant pastoral population of Tutsi.Livestock is the key activity for agriculture. Farmers cul-tivate staple crops (potatoes, beans, cassava etc.) andindustrial crops such as cotton.

Survey implementationSurvey implementationSurvey implementationSurvey implementationSurvey implementationPests and their natural enemies were surveyed

during the two cropping seasons of each year of 2000and 2001. Ten farms were selected randomly alongroads in the villages. Agreements were made with own-ers of the farms so that we could more easily conductthe surveys on their farms. Time was taken to explainto farmers the value of the survey; once the farmer wasconvinced, thereafter, he could involve himself in thesurvey-work on his garden. Each selected cotton farmwas divided into sections to facilitate the survey. Plants,leaves, fruits, flowers, stems and roots were inspected.Collection techniques included pitfall traps for spiders,earwigs, ground beetles, ants predators and other sur-face moving arthropods and sweep nets for moths,

13471347134713471347

World Cotton Research Conference-3 2003Cape Town - South Africa

dragonflies and butterflies. Rodents were captured us-ing traditional traps. Traps were set in farms andchecked at a regular interval of two weeks. Arthropodscaptured were kept in alcohol in tubes and brought atthe laboratory for identification. Pupae, larvae and eggsof pests found, were brought to the laboratory, andreared thereon local or artificial diets until parasitoidsemerged, and thereafter parasitoids were collected andsaved in alcohol. In order to facilitate the identificationof certain pest species, some lepidopterans caught aslarvae, were reared to adults. The identification of thepests and their natural enemies involved one of theguides (Autrique and Perreaux, 1989; Cauquil, 1986;Coulloud, 1989) and comparison to specimens kept atthe Museum of Natural Science, and at the Entomol-ogy laboratory of the National Centre for Research inNatural Sciences, CRSN-Lwiro, D.S. Bukavu, Kivu,DRCongo. When necessary, unidentified natural en-emies were saved in alcohol and sent to CAB Interna-tional UK, for proper identification.

Results and DiscussionResults and DiscussionResults and DiscussionResults and DiscussionResults and Discussion

A checklist of pests and natural enemies found ispresented in Table 1. It can be seen that the entomo-fauna of various cotton ecosystems of Ruzizi plain, isvery diversified. Most of the species belong to the Lepi-doptera, Hemiptera, Heteroptera, Dyctyoptera, Co-leoptera, Orthoptera, Homoptera, Diptera and Hy-menoptera (Table 1). The distribution of the speciesvaried. Some species were common in all sites, whilethe habitat of others was restricted to certain sites. Therelative abundance varied considerable from an areato another one. The population density of ladybirds washigh in all the sites surveyed.

Pest activities and injury levels on farms varied.Each pest species had a period when it could causeinjury, serious damages and losses in cotton produc-tion. For example, rodents were more active betweenOctober and December and between April and May ofeach year (Table 2). At these periods, farmers reportedexperiencing significant damage leading to consider-able yield loss of cotton seeds due to rodent attacks(Table 2). Significant attacks of cotton by pests wereseen in Kiliba, Luvungi and Lemera. Ladybirds, spi-ders and ground beetle predator species were abun-dant in most of the sites surveyed (Table 3). Their abun-dance was apparently enough to be able to controlaphid population to a significant extent.

The parasitism of aphids (Aphis gossypii) byBraconidae was very low and not sufficient to controlprey populations. From this preliminary survey con-ducted, it was observed that predators could be inte-grated into IPM system development for DRCongo cot-ton pest management, because their abundance wasrelatively high. The percentage of parasitism was verylow, therefore it is difficult to integrate them into theIPM system for the Ruzizi plain.

In the future, it will be necessary to establish thefeeding behavior of different predators observed, un-der laboratory and field conditions, in order to deter-mine the population density of a predator species thatcan control a given population of a pest species.

AcknowledgementAcknowledgementAcknowledgementAcknowledgementAcknowledgement

I am very grateful to the �Institut TechniqueAgricole de Kasenga�, Uvira, Ruzizi Plain, for technicalassistance during fieldwork. I thank Dr Joubert, WCRC-3 Conference chairman for sponsoring my participa-tion.

ReferencesReferencesReferencesReferencesReferences

� Autrique, A. and Perreaux, D. (1989). Maladies etravageurs des cultures de la région des grands lacsd�Afrique Centrale, AGCD-ISABU, pp 232.

� Anonymous, (1983). La sélection et l�améliorationdu cotonnier en RDCongo. Rapport Technique duCentre de Recherche de l�INERA à Gandajika,INERA-Kinshasa, RDCongo, pp. 357.

� Ahanchédé, A. (2000). Compétition entremauvaises herbes et culture cotonnière: influencedu nombre de sarclages sur la biomasse et lerendement. Tropicultura, 1818181818: 148-151.

� Cauquil, J. (1986). Maladies et ravageurs ducotonnier en Afrique au Sud du Sahara, IRCT-CIRAD-CFDT, France, 92 pp.

� Coulloud, (1989). Hétéroptères déprédateurs ducotonnier, Coton et Fibers Tropicales, France,200pp.

� Decaene, R. (1948). Méthodes statistiques pourl�étude des essais de rendements cotonnier àBambesa. Bulletin Agricole du Congo Belge, 3939393939:802-818.

� Echekwu, C.A. (2001). Correlations and correlatedResponses in upland Cotton (Gossypium hirsutumL.). Tropicultura, 1919191919: 210-213.

� Finley, K.W. and Wilkinson, G.N. (1963). The analy-sis of adaptation in plant breeding program. Aus-tralian Journal Agric. Research, 1414141414: 742-754.

� Fisher, M. (1917). Culture du cotton au Congobelge. Ferme expérimentale de Loukala (sankuru).Bulletin Agricole du Congo Belge, 77777: 29-37.

� Jurion, F. (1941). Quelques considérations surl�orientation de la sélection cotonnière au Congobelge. Bulletin Agricole du Congo Belge, 3232323232: 677-713.

� Knaff, E.E.A. (1946). Méthodes culturalescotonnières du milieu indigène dans le Bas-uélé.Bulletin Agricole du Congo Belge, 3737373737: 816-821.

� Miller, A. J. (1984). Selection of subsets of regres-sion variables( with discussion). Journal of the RoyalStatistical Society, A147A147A147A147A147: 389-425.

� Munyuli Bin Mushambanyi, T. (2002). Contributionà la promotion de la culture du blé (Triticum eastivumL.) au Sud-Kivu, République Démocratique duCongo: Evaluation du potentiel de rendement de 2

13481348134813481348


génotypes d�origine Burundaise, dans différenteszones agro-écologiques locales. Tropicultura, 2020202020(4): 210-216.

� Querton, (1925). Rapport sur la propagationcotonnière dans le district du Sankuru. BulletinAgricole du Congo Belge, B16B16B16B16B16: 347-353.

� Stener, (1927). Rapport mycologique sur lacampagne cotonnière de 1927 au Manièma et auKivu, Bulletin Agricole du Congo Belge, 8 8 8 8 8: 529-551.

� Vandenput, R. (1981). Les principales cultures enAfrique centrale, AGCD, Bruxelles, Belgique, p: 857-896., AGCD, Belgique, Bruxelles, 1252 pages.

Figure 1. Figure 1. Figure 1. Figure 1. Figure 1.Map of Demo-cratic Republicof Congo (Ruziziplain is shownbetween the twopoints). Anarrow indicatesthe survey area.

13491349134913491349


TT TTTable 1.able 1.able 1.able 1.able 1.List of pests and natural enem

ies found during the survey, in Ruzizi Plain, Eastern DR C

ongo, 2000-2001.

13501350135013501350


TT TTTable 1.able 1.able 1.able 1.able 1.

Contd.

13511351135113511351


TT TTTable 2.able 2.able 2.able 2.able 2.Relative im

portance of pests at different growth periods of cotton in rural areas of Ruzizi plain, K

ivu, DR C

ongo.

13521352135213521352


TT TTTable 3.able 3.able 3.able 3.able 3.Relative tim

ing of natural enemies at different sam

pling periods in Ruzizi plain in Kivu, Eastern D

R Congo (200-2001).

inventory of pests and natural enemies on cotton in ... · wars among other factors. surveys showed...

Documents